In some commercial and retail settings, there is a need to sort multiple print jobs. For example, a retail photo printer will need to place different customer print jobs in different bins to keep them separated. In another example, a shared resource, such as a copying machine or work group printer, will need to place different print jobs in one of a number of different empty bins, trays or slots. In each instance it is necessary to determine whether a bin, tray or slot is empty before placing a set of prints or a print job into the bin, tray or slot. This assures that the prints or the print job in the slot is for one customer or user and will prevent someone from getting someone else's prints or print job. Furthermore, for order management, it is necessary to know which bins contain jobs, when the job is removed, and if any prints were left behind, as well as which bins are empty and available to receive a new print job. It is also necessary to determine when the bin is empty so that another print job can be placed in the bin. In addition, if the print job is finished, an operator or picker can be prompted to empty a bin. The same will happen if a bin is not totally empty.
In addition to print sorters, there may also be other sorters for copy jobs and the like. Sometimes mechanical sensors or electromechanical sensors are used to detect when a bins if a bin contains materials. Mechanical sensors or electromechanical sensors are less than totally reliable. If the mechanical sensor or electromechanical sensor is required to move with a bin, slot or tray, the mechanical or electromechanical sensor is more prone to failure and, therefore, less reliable. Contacts associated with wires may fail, wires may fail, and moving mechanical devices are prone to failure. If the mechanical sensor is powered by an electrical source, consistently powering a sensor that requires power while moving one or more of a set of bins also can be a challenge.
The description set out herein illustrates the various embodiments of the invention and such description is not intended to be construed as limiting in any manner.